0.7.2-preview

Added

• api: open API to copy and paste material properties of MaterialSwitchClip
• doc: add TableOfContents structure and installation page
• doc: add documentations on MaterialSwitchClip

Changed

• deps: use com.unity.selection-groups@0.7.3-preview
• refactor: rename MaterialSwitchUtility (obsolete) to MaterialSwitchEditorUtility

Fixed

• fix: null error of activeMaterials in MaterialSwitchClipEditor